Lymphoid Images Flashcards
What organ is this?

Normal thymus
What organ is this?

Normal thymus
Name this region of the thymus

Cortex
Name this region of the thymus

Medulla
Name this structure and region within the thymus. What types of cells is this structure comprised of?

Hassall’s corpuscle within the medulla - comprised of thymic epithelial cells that contain coiled layers of keratin
Which region of the thymus is rich in T cells?
Medulla
Name this pathologic process and etiology

Thymic atrophy due to parvovirus
Other causes: viral, glucocorticoids, nutritional deficiency, toxins
Name this pathologic process and etiology

Thymic enlargement = thymoma
This is a histologic image of a thymoma. What is the main cell type?

Epithelial cells
What organ is this?

Normal spleen
What organ is this? ID the red, purple and pink areas.

Spleen
Red = red pulp
Purple = white pulp
Pink = fibrous capsule
What organ is this? ID the purple and red regions. What do these regions supply?

Spleen
Red = red pulp = RBC, macrophages (vascular)
Purple = white pulp = B and T cells (lymphoid)
Name the pathologic process and etiology

Uniform splenomegaly due to congestion
Name the pathologic process and etiology

Uniform splenomegaly due to septicemia
Name the pathologic process and etiology

Splenomegaly due to histoplasmosis
Name the pathologic process and morphologic dx?

Splenomegaly with chronic diffuse granulomatous splenitis
Name the etiology

Hemangioma
Name the pathologic process and etiology

Splenic nodule
Hemangioma
Name the pathologic process and etiology

Splenic nodule
Hemangiosarcoma
This is from a splenic nodule. What is the likely etiology?

Hemangiosarcoma
Name the pathologic process and etiology

Splenic nodules/masses
Hemangiosarcoma
Name the pathologic process and etiology

Splenic nodule
Splenic infarct with thrombus

Name the pathologic process and etiology

Splenic nodular hyperplasia

This is a histopath image from the spleen. Name the etiology.

Splenic nodular hyerplasia
Name the pathologic process and etiology

Splenic nodules/mass
Splenic metastatic carcinoma
Name the pathologic process and etiology

Splenic nodules
Splenic siderotic plaques
Common in old dogs

Splenic rupture
What organ is this?

Normal lymph node
Name this region of the lymph node. What does it contain?

Cortex
Follicles with B cells
Name this region of the lymph node

Medulla
Name this region of the lymph node. What is the predominant cell here?

Medullary cord
Plasma cells
Increase with immune stimulation
Label the areas of the lymph node. What do each of these areas do/contain?

- Capsule = fibrous connective tissue
- Subcapsular sinus = space that receives afferent lymph
- Parafollicular zone = densely cellular area between follicles and medulla – contains T cells
- Medullary sinuses = spaces containing macrophages and small lymphocytes – number of macrophages will increase when inflammation occurs

What is this staining for in the lymph node?

B cells stain brown – in follicular and medullary cords
T cells stain red – in parafollicular zone


Lymph node


Lymph node

Name the pathologic process and etiology. What are the causes?

Lymphadenomegaly/lymphadenopathy
Lymphadenitis
Causes: infectious, immune, toxic etiology
Give the morphologic diagnosis.

Acute suppurative and hemorrhagic lymphadenitis
Give the morphologic diagnosis.

Acute suppurative and hemorrhagic lymphadenitis
Note: lymphotes, necrotic cells

Name the pathologic process, etiology and duration

Lymphadenomegaly/lymphadenopathy
Lymphadenitis
Chronic (more remodeling)
Name the pathologic process, etiology and causes
Lymphadenomegaly/lymphadenopathy
Lymphoid hyperplasia
Causes: Ag stimulation, viral infection - Malignant catarrhal fever, BLV, FIV
Name the pathologic process, etiology and causes

Lymphadenomegaly/lymphadenopathy
Lymphoid hyperplasia
Causes: Ag stimulation, viral infection - Malignant catarrhal fever, BLV, FIV
Name the pathologic process and etiology

Lymphadenomegaly/lymphadenitis
Lymphoma
Name the pathologic process and etiology

Lymphadenomegaly/lymphadenitis
Lymphoma
Name the pathologic process and etiology

Lymphadenomegaly/lymphadenitis

Lymphoma
Name the pathologic process and etiology

Lymphadenomegaly/lymphadenitis
Multicentric Lymphoma in dogs
Name the organ and disease

Liver
Lymphoma

Name the organ and disease

Spleen
Lymphoma with siderotic plaques
Name the disease and distribution.
This is the most common form in this species

Alimentary lymphoma in cats

Name the disease and species

Lymphoma in cats

Name the disease and species

Lymphoma in cats
Name the disease and species

Lymphoma in cats
Name the disease and species

Lymphoma in cats
Name the disease and species

Lymphoma in cats
Name the disease and species

Lymphoma in cats
Name the disease and species

Lymphoma in cats
Name the distrubution, disease and species

Alimentary lymphoma in cats
Name the distrubution, disease and species

Alimentary lymphoma in cats

Name the disease and species

Lymphoma in cattle
Name the distribution, disease and species

Multicentric lymphoma in cattle
Abomasum
Name the distribution, disease and species

Multicentric lymphoma in cattle
Right atrium
Name the distribution, disease and species

Calf lymphoma in cattle
Bone marrow
Name the distribution, disease and species

Multicentric lymphoma in cattle
Spinal epidural fat
Name the pathologic process and etiology

Lymph node atrophy due to canine distemper virus
Note: reduced number of cell density, # of lymphocytes, normal structures not discernable

Lymph node atrophy due to distemper virus. What is missing?

Medullary cords

- Dog presented with enlarged LN, splenomegaly, neuro signs: collapse, weakness
- Necropsy: generalized LN enlargement, hepatomegaly, splenomegaly
- LN were large, off-white on cut surface, loss of cortex and medulla
- Name the distribution and disease

Multicentric lymphoma
This is multicentric lymphoma in a dog. What are some notable histological features that confirm this diagnosis?

- Loss of normal architecture
- Monomorphic medium-sized lymphocytes
- Lymphocytes extend beyond capsule into perinodal tissue
- Lymphocytes have coarse, marginated chromatin, prominent nucleoli, mild anisocytosis/anisokaryosis and frequent mitotic figures

- Dog presented with enlarged LN, splenomegaly, neuro signs: collapse, weakness
- Necropsy: generalized LN enlargement, hepatomegaly, splenomegaly
- LN were large, off-white on cut surface, loss of cortex and medulla
- Name the organ, distribution and disease.
- Which areas are expanded?

Multicentric lymphoma
Expanded white pulp areas contain medium sized lymphocytes

This is a lymph node. Give the morphologic diagnosis.

Chronic pyogranulomatous lymphadenitis
This is a lymph node. Give the morphologic diagnosis.
What type of cells are present?

Chronic pyogranulomatous lymphadenitis
Macrophages, fibroblasts, lymphocytes, neutrophils

Name the pathologic processes/diseases.

Lymph node hyperplasia - B and T cell expansion
- Enlargement and hypercellularlity of cortical follicles, parafollicular areas and medullary cords
Metastatic oral squamous cell carcinoma
This sample is from an animal with both lymph node hyperplasia and met oral squamous cell carcinoma. Which pathologic process does this area represent?

Lymphoid hyperplasia

This sample is from an animal with both lymph node hyperplasia and met oral squamous cell carcinoma. Which pathologic process does this area represent?

Met oral SCC

Name the organ, pathologic process and etiology

Spleen
Splenic nodules/masses - blood-filled
Hemangiosarcoma

This sample is from a spleen with nodules that were bloody when cut on surface. What is the etiology? What are some features that confirm this diagnosis?

Hemangiosarcoma
- Well demarcated mass with blood-filled spaces in the mass – variable in size and lined by epithelial cells
- Small caliber vessels in the mass are lined by endothelial cells with high nuclear/cytoplasmic ratios, moderate anisocytosis and anisokaryosis and frequent mitotic figures
